In 1991 the population of a town was a perfect square. Ten years later, after an increase of 60 people, the population was 16 more than a perfect square. Now, in 2011, with an increase of another 36 people, the population is once again a perfect square. Which of the following is closest to the percent growth of the town's population during this twenty-year period?
85
90
95
100
105
